Engine manufacturing process



Nov. 1, 1955 J. D. TURLAY 2,722,049

ENGINE MANUFACTURING PROCESS Filed NOV. 19, 1952 2 Sheets-Sheet lINVENTOR ATTORNEYS Nov. 1, 1955 J. D. TURLAY ENGINE MANUFACTURINGPROCESS 2 Sheets-Sheet 2 Filed NOV. 19, 1952 INVENTOR ATTORNEYS UnitedStates Patent ENGINE MANUFACTURING PROCESS Joseph D. Turlay, Flint,Mich., assignor to General Motors Corporation, Detroit, Mich., acorporation of Delaware Application November 19, 1952, Serial No.321,348 Claims. (or. 29-428) This invention relates to internalcombustion engines and to a process for manufacturingengines of thistype and havingv different piston displacement.

It has been the practice heretofore when building internal combustionengines of different sizes and horsepower to build the engines either ofnon-identical parts or if certain identical parts are used then it iscustomary to disable the smaller engines so that full horsepower cannotbe developed. This. is. generally done by employing; restrictions of onekind or another to impair the volumetric efliciency of the smallerengines. This reduces the power but it also impairs the efliciency bydecreasing the compression ratio of the smaller engines and isthereforev objectionable.

It is proposed to construct engines: of different horsepower by changingthe: displacement in engines, the principal parts of which areidentical. It is: proposed to construct pistons and cylinders whichdiffer principally in diameter and: form thereby changing, thedisplacementto produce engines of different. horsepower. It is proposedto use identical. crankshafts in such. engines; of differentdisplacement and to compensate for the difference in weight of thepistons by employing flywheels and fan pulleys on opposite ends of thecrankshafts, which are capable of compensating. for orcounter-balancing: the unbalanced weight resultingfrom the differentsizes of pistons employed; It is alsoproposed to use pistons; withdifferently formed ends to maintain the same: compression ratio in theengines of different displacement.

In the drawings;

Figure 1 represents afragment-ary' endelevational view of an engine oflarger displacement and with parts thereof broken away and shown incross" section internally of the engine.

Figure 2 is a fragmentary view of the] fan pulley employed on the frontend' of the engine disclosed by Figure 1.

Figure 3 is an elevational view of a flywheel employed on the rear endof the crankshaft with which the engine disclosed by Figure 1 may beprovided.

Figure 4 is a view of an engine of smaller displacement and showingparts of the engine structure in cross section.

Figure 5 is an elevational view of an engine flywheel which may beemployed on the rear end of the crankshaft of the engine disclosed byFigure 4.

Figure 6 is a fragmentary view illustrating in longitudinal sectionparts of the crankshafts and the flywheels extending beyond the rearmain bearings of the engines disclosed by Figures 1 and 4.

In Figures 1 and 4 V-type internal combustion engines 10 and 11 areconstructed in such manner that the engine 10 is of greater displacementand horsepower than the engine 11. However, the engines 10 and 11 mayhave identical head assemblies 12, identical inlet manifold andcarburetor assemblies 13, identical valve actuating mecha-.

except that the cylinders 19 and 21- may be. constructed of differentdiameters in similar or identical blocks 17 and 18-. The cylinders 19may be made larger in diam.- eter than the cylinders 21 so that largerpistons 22 may be employed in the cylinders 19 and smaller pistons 23maybe employed in the. cylinders 21. The cylinders 19 and 21 may beconstructed in otherwise identical blocks 17 and 18 either byconstructing the wall thickness; of the cylinders in the block 18:oversize or by constructing the. cylinders. of the same wall thicknessbut of different diameters. If the cylinders 21 in the. block, 18 areconstructed of a wall thickness greater-than may be required;

for the diameter of the cylinders 21 then the cylinders. 19 in.- theblock 17 simply may be bored to a larger diameter corresponding to thediameter of the cylinder 19'. The pistons 22 and 23 in. engines. 10. and11 are: all. connected to identical. crankshafts 16 by identicalconnecting rods 24. The rear ends of the crankshafts 16 are, adapted tohave flywheels 26 and 27 secured thereto. beyond therear main bearingsof the engines. 10- and 11. The flywheels 26 and 27 are. identical inevery respect except that the. flywheels 26 have openings 28 formed onone side thereof which cause the. flywheels 26 to be statically anddynamically unbalanced. Except for the openings 28 in the flywheels 26the flywheels 26- and 27 are statically and dynamically balanced. Thefront ends of. the. crankshaft 16 of the engines 10v and 11 are adaptedto. have. secured.

thereon fan drive pulleys indicated at 29 and 31.. The

drive; pulleys. 29 for the engines 10 are statically and. dynamicallyunbalanced due to the. formation of the pulleys. in. such manner as. to.provide unbalanced weights 32. on one side. thereof. The drive, pulleys31 are. statically and dynamically balanced. The crankshafts16. areformed in such a way as to provide crank arms 33 which areadapted to be.opposed by counterweights; 34. The counterweights 34 are formed in suchmanner as to statically and dynamically balance the crank arms 33, theconnecting rods 2.4 and the pistons. 23 for the engines of smaller dis,-placement 11. Since the flywheels 27 and the. fan pulleys 31 which areemployed on the: ends. of the crankshafts for the engines 11 are alsostatically and dynamically balanced it will be apparent that the engines11 will operate in balance when the crankshafts 16 are: rotated. by thevmovement of the pistons 23.

Notwithstanding the fact that identical crankshafts 16 are employed inthe engines 10 having pistons 22 that. are larger and heavier than thepistons 23' in the engines. 11 the engines 10 also will operate inbalance when the crankshafts 16" are rotated. The imperfect balance ofthe crankshafts 16 with the heavier pistons 22 is compensated for by thestatically and dynamically unbalanced flywheels 26 at the rear ends ofthe shafts 16 and the statically and dynamically unbalanced flywheelpulleys 29 at the front ends of the shafts 16. The flywheels 26 and thepulleys 29 are formed with unbalancing means 28 and 32 respectivelywhich is formed and positioned at such angles with respect to the axisof rotation of the shafts 16 as to properly balance the shafts 16 and tocompensate for the unbalance resulting from the employment of the shaftswith the larger and heavier pistons 22. Since the pistons 22 and 23 inthe cylinders 19 and 21 respectively are of different diameters it isnevertheless possible to have the same compression ratios in the engines10 and engines 11. Such difference in the diameters of the pistons 22and 23 may be compensated for by forming the outwardly projecting ends36 on the pistons 22 in such manner as not to project into thecombustion chambers 37 in the engines 10 as far as the outwardlyprojecting ends 38 on the pistons 23 project into the combustionchambers 39 of the engines 11. Such differences in the ends of thepistons 23 and 24 will provide the same com- Patented Nov; 1, 11955.

pression ratios in the engines and 11 without changing the cavities 41in the heads of the engines 10 and 11.

By practicing the invention it is possible to build engines of largerdisplacement and smaller displacement without materially changing any ofthe parts of the engines other than the pistons employed in thecylinders of the engines and the flywheels and fan pulleys employed onthe crankshaft of the engines.

I claim:

1. A process of manufacturing engines of different displacement whichcomprises constructing identical crankshafts for all of said engines,said crankshafts being statically and dynamically balanced for operationwith said engines of smaller displacement, constructing flywheels andfan belt pulleys for operation on the rear and front ends of saidcrankshafts respectively, said flywheels and fan belt pulleys for saidengines of smaller displacement being statically and dynamicallybalanced and said flywheels and fan belt pulleys for said engines oflarger displacement being statically and dynamically unbalanced, andassembling said engines with said statically and dynamically balancedflywheels and pulleys on said engines of smaller displacement and withsaid statically and dynamically unbalanced flywheels and pulleys on saidcrankshafts for said engines of larger displacement.

2. A process of manufacturing engines of larger and smaller displacementand comprising constructing iden tical crankshafts for said engines oflarger and smaller displacement, said crankshafts being statically anddynamically balanced for operation with said engines of smallerdisplacement, constructing different flywheels and fan belt pulleys forsaid engines, said flywheels and fan belt pulleys for said engines ofsmaller displacement being statically and dynamically balanced foroperation on said crankshaft without affecting the static and dynamicbalance of said crankshaft, said flywheels and pulleys for operationwith said engines of larger displacement being statically anddynamically unbalanced and to the extent necessary to compensate for thestatic and dynamic unbalance of said crankshafts when said crankshaftsare employed with said engines of larger displacement, and assemblingsaid engines with said statically and dynamically balanced flywheels andpulleys on said engines of smaller displacement and with said staticallyand dynamically unbalanced flywheels and pulleys on said engines oflarger displacement.

3. A process of manufacturing engines of different displacement whichcomprises constructing identical engine blocks except with respect tothe diameters of the cylinders formed in said blocks, constructingcertain of said cylinders with larger diameters for said largerdisplacement engines and certain of said cylinders with smallerdiameters for said smaller displacement engines, constructing pistons oflarger diameter for said cylinders of larger diameter and pistons ofsmaller diameter for said cylinders of smaller diameter, constructingidentical crankshafts for all of said engines, said crankshafts beingstatically and dynamically balanced for operation in said engines ofsmaller displacement, constructing statically and dynamically balancedengine flywheels and fan pulleys for operation with the crankshafts ofsaid engines of smaller displacement, constructing statically anddynamically unbalanced flywheels and fan pulleys for operation with saidengines of larger displacement, assembling said engines of smallerdisplacement with said pistons of smaller diameters in said cylinders ofsmaller diameters and said statically and dynamically balanced flywheelsand pulleys on the crankshafts of said engines of smaller displacementand assembling said engines of larger displacement with said pistons oflarger diameters in said cylinders of larger diameters and saidstatically and dynamically unbalanced flywheels and pulleys on thecrankshafts of said engines of larger displacement.

4. A process of manufacturing engines of different displacement whichcomprises constructing all of said engines by employing crankshafts ofidentical construction, constructing the engines of smaller displacementwith statically and dynamically balanced crankshaft and piston andconnecting rod assemblies, constructing the engines of largerdisplacement with statically and dynamically unbalanced crankshaft andpiston and connecting rod assemblies, and balancing said assemblies ofsaid engines of larger displacement by applying unbalanced counterweightmeans to the crankshafts of said engines of larger displacement.

5. A process of manufacturing engines of diflerent displacement whichcomprises constructing all of said engines by employing crankshafts ofidentical construction, constructing the engines of smaller displacementwith statically and dynamically balanced crankshaft and piston andconnecting rod assemblies, constructing the engines of largerdisplacement with statically and dynamically unbalanced crankshaft andpiston and connecting rod assemblies, and balancing said assemblies ofsaid engines of larger displacement by applying unbalanced counterweightmeans to the ends of the crankshafts of said engines of largerdisplacement which project beyond the end bearings for said crankshafts.

References Cited in the file of this patent UNITED STATES PATENTS1,428,620 Wilber Sept. 12, 1922 1,783,664 McGovern Dec. 2, 19302,450,701 Wahlberg Oct. 5, 1948 2,632,340 Dolza Mar. 24, 1953

